Optimal allocation of quantized human eye depth perception for multi-focal 3D display design.

Creating immersive 3D stereoscopic, autostereoscopic, and lightfield experiences are becoming the center point of optical design of future head mounted displays and lightfield displays. However, despite the advancement in 3D and light field displays, there is no consensus on what are the necessary quantized depth levels for such emerging displays at stereoscopic or monocular modalities. Here we start from psychophysical theories and work toward defining and prioritizing quantized levels of depth that would saturate the human depth perception. We propose a general optimization framework, which locates the depth levels in a globally optimal way for band limited displays. While the original problem is computationally intractable, we manage to find a tractable reformulation as maximally covering a region of interest with a selection of hypographs corresponding to the monocular depth of field profiles. The results indicate that on average 1731 stereoscopic and 7 monocular depth levels (distributed optimally from 25 cm to infinity) would saturate the visual depth perception. Such that adding further depth levels adds negligible improvement. Also the first 3 depth levels should be allocated at (148), then (83, 170), then (53, 90, 170) distances respectively from the face plane to minimize the monocular error in the entire population. The study further discusses the 3D spatial profile of the quantized stereoscopic and monocular depth levels. The study provides fundamental guidelines for designing optimal near eye displays, light-field monitors, and 3D screens.

Reduced loss aversion and inhibitory control in adolescents with internet gaming disorder.

As adolescents are in a crucial developmental period, they are more susceptible than adults to Internet gaming disorder (IGD). The dual-system model proposed by Casey, Jones, and Hare (2008) emphasized the equal importance of reward-seeking and cognitive control systems in accounting for adolescents' risky behaviors. Considering that no study has simultaneously examined reward seeking (loss aversion, i.e., loss sensitivity relative to gain sensitivity) and cognitive control (inhibitory control) in IGD, this study aimed to investigate loss aversion and inhibitory control in the same IGD adolescent population. Forty five adolescent patients with IGD and 43 matched healthy control participants completed a mixed gambles task and a stop-signal task to measure loss aversion and inhibitory control, respectively. Two main findings were identified in this study. First, the IGD participants showed concurrent reduced loss aversion and inhibitory control, suggesting that differences in both systems serve as behavioral markers of IGD in adolescents. Second, the IGD participants were categorized into 2 distinct subtypes based on differences in loss aversion and inhibitory control, which implies specific therapies for specific subtypes of IGD adolescents. Therefore, this study extends the application of the dual-system model to explain adolescents' excessive Internet gaming behavior. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Greater tolerance to losses in sensation seeking: Evidence from probability and delay discounting.

BACKGROUND: Sensation seeking is a behavioral endophenotype of substance use and is associated with abnormalities in financial reward processing. Previous research suggests that high sensation seekers (HSS) relative to low sensation seekers (LSS) show either an enhanced sensitivity to financial rewards or a reduced sensitivity to financial punishments. However, there are few studies investigating the valuation of financial rewards and punishments as a function of delivery probability and delay, two important aspects of reward processing that influence the valuation. METHODS: We administrated a probability discounting task and a delay discounting task to 56 HSS and 57 LSS selected from a large sample. Each task was crossed with two factors: valence (gain vs. loss) and amount (Ò°1000 vs. Ò°50000). RESULTS: For the probability discounting task, HSS discounted probabilistic losses but not gains more steeply than LSS, irrespective of the amount of outcome. For the delay discounting task, HSS discounted delayed losses more steeply than LSS, for the large but not small amount condition. In contrast, both groups exhibited comparable discounting rates for gains across the two amount conditions. These results remained significant when impulsivity levels were controlled for. CONCLUSIONS: Together, our data strengthen the argument that the dysfunctional valuation in sensation seeking is valence specific, which may be driven by a weaker avoidance system, rather than by a stronger approach system.

Deficits in voluntary pursuit and inhibition of risk taking in sensation seeking.

Sensation seeking has been associated with substance use and other risk-taking behaviors. The present functional magnetic resonance imaging (fMRI) study investigated the neural correlates underlying risk taking in sensation seeking. Twenty-eight high sensation seekers (HSS; 14 female and 14 male young adults) and 28 low sensation seekers (LSS; 14 female and 14 male young adults) performed an interactive, sequential gambling task that allowed for voluntary pursuit or inhibition of risk taking. Behaviorally, HSS versus LSS exhibited a stronger tendency toward risk taking. Comparison of the groups revealed that when taking risks, HSS relative to LSS exhibited reduced fMRI responses in brain areas involved in risk processing, such as the dorsomedial prefrontal cortex and the thalamus. Importantly, during the voluntary inhibition of risk taking, HSS relative to LSS showed greater fMRI responses in brain areas implicated in cognitive control (the bilateral anterior cingulate cortex) and negative emotion (the right anterior insula). These findings suggest that risk taking in sensation seeking may be driven by both a hypoactive neural system in the voluntary pursuit of risk taking and a hyperactive neural system in the voluntary inhibition of risk taking, thus providing implications for future prevention programs targeting sensation-seeking behaviors. Hum Brain Mapp 38:6019-6028, 2017. © 2017 Wiley Periodicals, Inc.

Learning the 3-D structure of objects from 2-D views depends on shape, not format.

Humans can learn to recognize new objects just from observing example views. However, it is unknown what structural information enables this learning. To address this question, we manipulated the amount of structural information given to subjects during unsupervised learning by varying the format of the trained views. We then tested how format affected participants' ability to discriminate similar objects across views that were rotated 90° apart. We found that, after training, participants' performance increased and generalized to new views in the same format. Surprisingly, the improvement was similar across line drawings, shape from shading, and shape from shading + stereo even though the latter two formats provide richer depth information compared to line drawings. In contrast, participants' improvement was significantly lower when training used silhouettes, suggesting that silhouettes do not have enough information to generate a robust 3-D structure. To test whether the learned object representations were format-specific or format-invariant, we examined if learning novel objects from example views transfers across formats. We found that learning objects from example line drawings transferred to shape from shading and vice versa. These results have important implications for theories of object recognition because they suggest that (a) learning the 3-D structure of objects does not require rich structural cues during training as long as shape information of internal and external features is provided and (b) learning generates shape-based object representations independent of the training format.

Problematic Internet Users' Discounting Behaviors Reflect an Inability to Delay Gratification, Not Risk Taking.

The relationship between impulse control disorder (ICD) behaviors and problematic Internet use (PIU) has been established in the literature. Our aim was to further investigate whether the ICDs of individuals suffering from PIU primarily involve an inability to delay gratification or a tendency to take risks. Using delay and probability discounting tasks, we compared the subjective value of discounting between PIU individuals and controls in conditions of gaining or losing different monetary amounts. The results of the present study revealed a significant positive relationship between PIU and impulsivity scores. PIU individuals discounted delayed amounts more steeply than controls, regardless of the reward sign and monetary amount. Conversely, there were no significant group differences in the probability discounting task. These findings suggest that PIU individuals may be more impulsive than controls when impulsivity is framed as insensitivity to delayed outcomes rather than as a tendency to take risks, which is inconsistent with the view of impulsivity as a general trait.

Spatiotemporal information during unsupervised learning enhances viewpoint invariant object recognition.

Recognizing objects is difficult because it requires both linking views of an object that can be different and distinguishing objects with similar appearance. Interestingly, people can learn to recognize objects across views in an unsupervised way, without feedback, just from the natural viewing statistics. However, there is intense debate regarding what information during unsupervised learning is used to link among object views. Specifically, researchers argue whether temporal proximity, motion, or spatiotemporal continuity among object views during unsupervised learning is beneficial. Here, we untangled the role of each of these factors in unsupervised learning of novel three-dimensional (3-D) objects. We found that after unsupervised training with 24 object views spanning a 180° view space, participants showed significant improvement in their ability to recognize 3-D objects across rotation. Surprisingly, there was no advantage to unsupervised learning with spatiotemporal continuity or motion information than training with temporal proximity. However, we discovered that when participants were trained with just a third of the views spanning the same view space, unsupervised learning via spatiotemporal continuity yielded significantly better recognition performance on novel views than learning via temporal proximity. These results suggest that while it is possible to obtain view-invariant recognition just from observing many views of an object presented in temporal proximity, spatiotemporal information enhances performance by producing representations with broader view tuning than learning via temporal association. Our findings have important implications for theories of object recognition and for the development of computational algorithms that learn from examples.

Top-down processing of symbolic meanings modulates the visual word form area.

Functional magnetic resonance imaging (fMRI) studies on humans have identified a region in the left middle fusiform gyrus consistently activated by written words. This region is called the visual word form area (VWFA). Recently, a hypothesis, called the interactive account, is proposed that to effectively analyze the bottom-up visual properties of words, the VWFA receives predictive feedback from higher-order regions engaged in processing sounds, meanings, or actions associated with words. Further, this top-down influence on the VWFA is independent of stimulus formats. To test this hypothesis, we used fMRI to examine whether a symbolic nonword object (e.g., the Eiffel Tower) intended to represent something other than itself (i.e., Paris) could activate the VWFA. We found that scenes associated with symbolic meanings elicited a higher VWFA response than those not associated with symbolic meanings, and such top-down modulation on the VWFA can be established through short-term associative learning, even across modalities. In addition, the magnitude of the symbolic effect observed in the VWFA was positively correlated with the subjective experience on the strength of symbol-referent association across individuals. Therefore, the VWFA is likely a neural substrate for the interaction of the top-down processing of symbolic meanings with the analysis of bottom-up visual properties of sensory inputs, making the VWFA the location where the symbolic meaning of both words and nonword objects is represented.

Individual differences in holistic processing predict face recognition ability.

Why do some people recognize faces easily and others frequently make mistakes in recognizing faces? Classic behavioral work has shown that faces are processed in a distinctive holistic manner that is unlike the processing of objects. In the study reported here, we investigated whether individual differences in holistic face processing have a significant influence on face recognition. We found that the magnitude of face-specific recognition accuracy correlated with the extent to which participants processed faces holistically, as indexed by the composite-face effect and the whole-part effect. This association is due to face-specific processing in particular, not to a more general aspect of cognitive processing, such as general intelligence or global attention. This finding provides constraints on computational models of face recognition and may elucidate mechanisms underlying cognitive disorders, such as prosopagnosia and autism, that are associated with deficits in face recognition.

Extraversion predicts individual differences in face recognition.

In daily life, one of the most common social tasks we perform is to recognize faces. However, the relation between face recognition ability and social activities is largely unknown. Here we ask whether individuals with better social skills are also better at recognizing faces. We found that extraverts who have better social skills correctly recognized more faces than introverts. However, this advantage was absent when extraverts were asked to recognize non-social stimuli (e.g., flowers). In particular, the underlying facet that makes extraverts better face recognizers is the gregariousness facet that measures the degree of inter-personal interaction. In addition, the link between extraversion and face recognition ability was independent of general cognitive abilities. These findings provide the first evidence that links face recognition ability to our daily activity in social communication, supporting the hypothesis that extraverts are better at decoding social information than introverts.

Heritability of the specific cognitive ability of face perception.

What makes one person socially insightful but mathematically challenged, and another musically gifted yet devoid of a sense of direction? Individual differences in general cognitive ability are thought to be mediated by "generalist genes" that affect many cognitive abilities similarly without specific genetic influences on particular cognitive abilities [1]. In contrast, we present here evidence for cognitive "specialist genes": monozygotic twins are more similar than dizygotic twins in the specific cognitive ability of face perception. Each of three measures of face-specific processing was heritable, i.e., more correlated in monozygotic than dizygotic twins: face-specific recognition ability, the face-inversion effect [2], and the composite-face effect [3]. Crucially, this effect is due to the heritability of face processing in particular, not to a more general aspect of cognition such as IQ or global attention. Thus, individual differences in at least one specific mental talent are independently heritable. This finding raises the question of what other specific cognitive abilities are independently heritable and may elucidate the mechanisms by which heritable disorders like dyslexia and autism can have highly uneven cognitive profiles in which some mental processes can be selectively impaired while others remain unaffected or even selectively enhanced.